Screw thread comparator



Feb. 19, 1952 5 w sw so 2,586,114

SCREW THREAD COMPARATOR Filed Feb. 16, 1945 I I 5 25 a 23 l l 26 a i ,0

ATTORNEY Patented Feb. 19, 1952 UNITED STATES ATENT OFFICE SCREW THREAD COMPARATOR Bror W. Swanson, Elmwood, Conn., assignor, by mesne assignments, to Anthony F. Kasprow, Felix A. KasproW, Joseph W. Kasprw, Ste phen G. Kasprow, New Britain, Conn., and Meyer E. Bailey, New Haven, Conn.

Application February 16, 1945, Serial No. 578,323

8 Claims. (ores-+199) My invention relates to the class of devices that are employed for determining the condition of screw threads as to form, and an object of the invention, among others, is the provision of a device of this sort that is simple in construction and particularly accurate in the functions performed by it.

One form of a device embodying the invention and in the construction and use of which the objects herein set out, as well as others, may be attained is illustrated in the accompanying drawings, in which Figure 1 is a front view of a comparator embodying my invention. v

Figure 2 is a view in side elevation of .the same with parts broken away to show construction.

In the accompanying drawings the numeral 5 denotes a base of the comparator which maybe of any suitable form to support a column 6 rising from the base and having a recess 1 formed in one side and extending laterally therein. A

shank 8 of a support 9 extends into the recess 7. Holding rods IG| I extend in opposite directions from the top and bottom within bores in the column 6 that extend into the recess 1, the ends of such rods being engaged by ball bearings I2 located in recesses in the ends of the rods and in recesses in opposite sides of the shank 8, as shown in Fig. 2 of the drawings. The recess 1 is flared at its mouth so that the support 9 may be swung from side to side for a limited distance.

The support 9 is of u-shape, one arm [3 comprising an anvil for a die M which has a screw thread for engaging the thread of a separate member. The said die M has a groove Ma which separates the two rests l5, l5 of the die and thereby provides a two point support for the piece of work being gauged and preventsany foreign particles which would prevent accurate gauging from resting in the thread of the die I l. The other arm of the support comprises a head 16 in which is located a plunger l! with a die 3 which conforms to the screw thread on the piece of work to be gauged and is formed opposite to that of the die l4 so that when the screw threaded piece rests in the die I4 on one side the opposite side of said thread will conform to and rest in the die I8. The plunger H with the die 18 thereon is pressed toward the die H! as by means of a spring l9 confined within the head 16 by means of a cap 20. The die I8 is thus held pressed against a piece of work 2| being operated upon by the machine and a lever 22 is employed to move the die [8 away from the work piece -to-.release the latter and free it for i p t n,

It will benoted that when the piece of work 2i i being gauged between the dies I4 and Is it is supported with a three point contact that is provided by the two portions 15, I5 and the die [8 and permits accurate gauging operation.

A dial indicator 23 is supported at the end of a rod 24 projecting fromthe top of the column 6, this indicator comprising adial 25 for determining the condition of the work to be tested. A stem.26 for actuating the pointer within the indicator extends downwardly into contact with the plunger I! which as hereinbefore stated is supported by the lever 22. p

the operation of the device the handle 21 of the lever 22' is pressed downward and this separates the dies l 4 -|8 and the pointer of the compensator moves to an inactive position. During this operation they support 9 is swung laterally to one side, as shown in dotted outline in Fig. 1 of the drawings, as a convenient position for placing the work piece for operation upon it. This support may be retained in its normal position as shown in Fig. '2. In either instance it will be noted that the threaded piece to be tested may be presented to and engaged with the dies by moving the threads in the direction of extension of the threads so that thet-hreads readily enter the grooves between the dies, and this case of engagement of the threads of a work piece with the threads of the dies is a most important feature. Again the possibility of swinging the support to'one side or the other is 'an important feature in the operation of the device owing to the facility with which the work pieces may be placed in position and then tested by release of the lever 22 to permit the stem' 25 to allow operation of the pointer 28 to denote the condition of the threads of the work piece in a manner that will be readily understood.

' I claim:

'1. A' comparator for testing the condition of threads on articles and including a jaw shaped support having rigid jaws forming an opening between them for the reception of the articles to be tested,'dies formed to fit threads on said articles, at least one of said dies being movable in ajaw of said support, a sliding plunger associated with said movable die, gauge means operable by said plunger and aline'd therewith for indicating the distance between said dies and means for mounting the jaw-shapedsupport for horizonal ly swinging movements whereby the support may be laterally displaced relative to said gauge means for' placement of an article therein to be tested.

2. A comparator for testing the condition of threads on articles and including a column rising from a base, a jaw shaped support with rigid jaws extending from said column, dies supported on opposite faces of said jaws and formed to fit the said threads, at least one of said dies being movable in said jaws, means for separating said dies for the reception of said articles, an indicator for indicating the distance between said dies, and means mounting said support on said column for movement about a vertical axis for the swinging of said support from side to side relatively to said indicator.

3. A comparator for testing the condition of threads on articles and including a vertical column rising from a base and having a recess in the side thereof, a jaw shaped support having rigid jaws with dies therein and having a shank extending into said recess, longitudinally extending rods in said column and engaging said shank from opposite sides thereof to provide a vertical pivot and retain the support in position, an inrods and shank, threaded means for adjustably positioning said rods to retain said balls in contact with said shank to permit horizontal pivotal movement thereof within said opening, and an indicator on the column above the gauge and operable by said gauge for indicating the distance between said dies.

5. A comparator for testing the condition of threads on articles and including a column rising from a base and having a recess in one side thereof, a jaw-shaped support having rigid jaws and a shank extending into said recess and pivotally mounted therein for horizontally swinging movements, a pair of dies oppositely sup orted in said aws, one of said dies being movable in a jaw relative to the opposite die, spring means including a sliding plunger urging said movable die in the direction of the opposite jaw, means for moving the movable jaw and plunger in opposition to said spring means and an indicator on the column above the jaw shaped support and inc uding a sliding plunger adapted to be en aged by the plun er of said spring means for indicating the distance between said jaws.

6. A comparator for testing the condition of thr ads on articles comprising a base, a column carried by said base, a support ositioned transverselv of said column and mounted on said column for swin ing movement about a vertical axis, a pair of ri id jaws spaced vertically from each other on said support. coacting dies formed to fit threads on said articles interposed between said jaws, one of said dies being fixedly supported in one of said jaws and the other of said dies being mounted in the other of said jaws for movement toward and away from said fixed die, and gauge means carried by said column engageable with said movable die and operable in response to the movement of said latter named die-away from said fixed die for indicating the distance between said dies.

7. A comparator for testing the condition of threads on articles comprising a base, a column carried by said base, a support positioned transversely of said column and mounted on said column for swinging movement about a vertical axis, a pair of rigid jaws spaced vertically from each other on said support, coacting dies formed to fit threads on said articles interposed between said jaws, one of said dies being fixedly supported in one of said jaws and the other of said dies being mounted in the other of said jaws for movement toward and away from said fixed die, gauge means carried by said column engageable with said movable die and operable in response to the movement of said latter named die away from said fixed die for indicating the distance between said dies, and spring means operatively connected to said movable die for urging the latter die toward said fixed die.

8. A comparator for testing the condition of threads on articles comprising a base, a column carried by said base, a support positioned transversely of said column and mounted on said column for swinging movement about a vertical axis, a pair of rigid jaws spaced vertically from each other on said support, coacting dies formed to fit threads on said articles interposed between said jaws, one of said dies being fixedly supported in one of said jaws and the other of said dies 1 being mounted in the other of said jaws for movement toward and away from said fixed die, gauge means carried by said column engageable with said movable die and operable in response to the movement of said latter named die away from said fixed die for indicating the distance between said dies, spring means operatively connected to said movable die for urging the latter die toward said fixed die, and hand actuable means exteriorly of said jaws and operatively connected to said movable die for moving the latter die against the tension of said spring means away from said fixed die.

BROR W. SWANSON.

REFERENCES CITED The following references are of record in the file of this patent:

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